Themes don't update codeblocks, so they look a little blinding in night mode

[Nemo157]

This doesn't update codeblocks, so they look a little blinding in night mode:

Could we fix that?

Originally posted by @jyn514 in #1116 (comment)

[Nemo157]

places with code blocks:

• /about/builds: https://docs.rs/about/builds
• Source pages: https://docs.rs/crate/libmtp-rs/0.7.1/source/Cargo.toml
• Crate readmes: https://docs.rs/crate/lapin/1.4.3